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基于BFO-LSSVM算法的爆破振动峰值速度预测

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长江技术经济 2022年第5期6卷 51-56页

作者：张国鹏赵根胡英国郑皓文饶宇杨招伟长江科学院水利部岩土力学与工程重点实验室武汉430010 河海大学土木与交通学院南京210098

钻爆法施工隧洞开挖往往面临复杂的围岩地质条件,采用传统的爆破振速预测方法难以得到准确的峰值振速,为此利用细菌觅食算法(BFO)优化最小二乘支持向量机(LSSVM)参数,以炮孔进深、距爆心水平距离、高程、最大单响药量、总药量为输入因子... 详细信息

钻爆法施工隧洞开挖往往面临复杂的围岩地质条件,采用传统的爆破振速预测方法难以得到准确的峰值振速,为此利用细菌觅食算法(BFO)优化最小二乘支持向量机(LSSVM)参数,以炮孔进深、距爆心水平距离、高程、最大单响药量、总药量为输入因子,峰值振速为输出因子,运用BFO-LSSVM模型预测爆破振动峰值速度。结合滇中引水工程昆明段下游引水隧洞主洞爆破开挖过程中30组现场爆破振动监测数据,分别采用BFO-LSSVM模型、LS-SVM模型和萨道夫斯基公式进行爆破振动速度预测,预测结果与实测值的平均相对误差分别为4.02%、12.18%、27.85%。结果表明BFO-LSSVM模型具有更显著的数据拟合能力,对于复杂地质条件下的隧洞开挖爆破振动峰值速度预测有更强的适用性。

关键词：菌群觅食算法最小二乘法支持向量机隧道开挖爆破振动速度预测精度

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抗滑桩开挖爆破振动对民房影响研究

重庆建筑 2022年第9期21卷 49-51页

作者：吴建兵杨招伟张文龙陈步高徐驰浙江华东工程咨询有限公司浙江杭州311121 长江水利委员会长江科学院湖北武汉430010 防灾减灾湖北省重点实验室(三峡大学) 湖北宜昌443002

白鹤滩水电站迁建集镇抗滑桩爆破施工期间,为确保周边民房等建筑物安全,减少因爆破振动导致的纠纷,开展了爆破振动监测和爆破对周边民房的影响研究。通过监测迁建集镇抗滑桩掏槽爆破时诱发的地表振动,探究在新建村方向的爆破振动传播衰... 详细信息

白鹤滩水电站迁建集镇抗滑桩爆破施工期间,为确保周边民房等建筑物安全,减少因爆破振动导致的纠纷,开展了爆破振动监测和爆破对周边民房的影响研究。通过监测迁建集镇抗滑桩掏槽爆破时诱发的地表振动,探究在新建村方向的爆破振动传播衰减规律;基于回归分析研究了不同爆心距处不同类型房屋的振动响应,提出了爆破振动控制标准。

关键词：白鹤滩掏槽爆破爆破振动控制标准影响评价

维普期刊数据库博看期刊

Sugar Starvation Enhances Leaf Senescence and Genes Involved in Sugar Signaling Pathways Regulate Early Leaf Senescence in Mutant Rice

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Rice science 2020年第3期27卷 201-214页

作者： LI zhaowei ZHAO Qian CHENG Fangmin College of Life Sciences Fujian Agriculture and Forestry UniversityFuzhou 350002China Institute of Crop Science College of Agriculture and BiotechnologyZhejiang UniversityHangzhou 310058China

To clarify the complex regulatory relationship between changes in sugar content and leaf senescence during the grain-filling stage of rice,genotype-dependent differences in sugar content and the temporal transcriptional patterns of genes involved in sugar signaling pathways were determined in mutant rice exhibiting early leaf senescence and its wild type Zhefu *** effects of exogenous glucose or sucrose on the senescence of detached leaves under dark conditions were also ***,soluble sugar,sucrose and fructose contents decreased,whereas electrolytic leakage and malondialdehyde levels increased in mutant leaves at the grain-filling *** results suggested that sugar starvation is positively correlated with the early leaf senescence of mutant *** leaf segments incubated in exogenous sugar solutions under dark conditions exhibited delayed *** high expression of Hxk1 in leaves of mutant plants at the initial grain-filling stage suggested that Hxk1 is involved in the hexose-sensing process at the early stage of leaf *** low expression levels of Hxk2 and Frk1 in the senescing leaves of mutant rice during the grain-filling stage are indicative of weakened hexose *** addition,the high expression levels of Su Sy1,Su Sy2 and Su Sy4 in leaves of mutant plants at the initial grain-filling stage are accompanied by the high transcript levels of SUT1,which favor sucrose translocation and remobilization from the early senescing leaves of mutant *** relatively reduced transcript levels of ch FBP,cy FBP,SPS1,SPS2 and SPS6 indicated that during the grain-filling stage,sucrose biosynthesis is weakened in the senescing leaves of mutant rice.

关键词： rice sugar starvation leaf senescence signaling pathway detached leaf segment grain-filling stage

Bioaccumulation and translocation of cadmium in cole (Brassica campestris L.) and celery (Apium graveolens) grown in the polluted oasis soil,Northwest of China

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Journal of Environmental Sciences 2011年第8期23卷 1368-1374页

作者： Yiming yang Zhongren Nan Zhuanjun Zhao zhaowei Wang Shengli Wang Xia Wang Wangqiang Jin Cuicui Zhao Key Laboratory of Western China's Environmental System Ministry of Education College of Resource and Environment Lanzhou UniversityLanzhou 730000 China. School of Chemical Engineering North West University for Nationalities Lanzhou 730030 China

A pot experiment was conducted to study the bioaccumulation and translocation of cadmium （Cd） in cole （Brassica campestris L.） and celery （Apium graveolens） grown in the Cd-polluted oasis soil, Northwest of China. The results showed that Cd in the unpolluted oasis soil was mainly bound to carbonate fraction （F2） and Fe-Mn oxide fraction （F3）. However, marked change of Cd fractions was observed with increasing soil Cd concentrations, in which the concentration of Cd in F1 （exchangeable fraction）, F2 and F3 increased significantly （p 〈 0.001 for F1, F2 and F3）. The growth of cole and celery could be facilitated by low concentrations of Cd, but inhibited by high cortcentmdons. The correlation analysis between the fraction distribution coefficient of Cd in the soil and Cd concentration accumulated in the two vegetables showed that Cd in F1 in the soil made the greatest contribution on the accumulation of Cd in the two vegetables. The high bio-eoncentration factor and the translocation factor of Cd in both cote and celery were observed, and Cd had higher accumulation in the edible parts of the two vegetables. Therefore, both cole and celery grown in Cd-polluted oasis soil have higher risk to human health. And the two vegetables are not suitable to be cultivated as vegetables consumed by human in the Cd-polluted oasis soil.

关键词： bioaccumulation translocation cadmium cole and celery oasis soil

微波消解-火焰原子吸收法测定貉毛中铜含量不确定度评定

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现代畜牧兽医 2016年第8期 13-17页

作者：杨赵伟闫玉杰赵雅楠邬溪芮李博杜顺丰河北省秦皇岛市农产品质量安全监督检验中心河北秦皇岛066000

微波消解-火焰原子吸收法测定貉毛中铜含量方法的准确度和精密度良好,通过分析影响测量不确定度的主要来源,对分析过程中的样品称量、样品前处理、标准溶液配制、标准曲线非线性引入的输入值、测量重复性和仪器本身等6个不确定分量进行... 详细信息

微波消解-火焰原子吸收法测定貉毛中铜含量方法的准确度和精密度良好,通过分析影响测量不确定度的主要来源,对分析过程中的样品称量、样品前处理、标准溶液配制、标准曲线非线性引入的输入值、测量重复性和仪器本身等6个不确定分量进行分析和合成,计算出铜的扩展不确定度,为系统分析检测结果的准确程度和方法的可靠性提供参考。

关键词：不确定度微波消解火焰原子吸收貉子

Soil Erosion on a Slope without Vegetation: a Simulating Experiment on a Bare Land in ***

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Wuhan University Journal of Natural Sciences 2004年第4期9卷 527-532页

作者： zhaowei HUKe KIMOTOAkitsu MIZUYAMATakahisa CollegeofEarthandSciences JilinUniversityChangehun130061JilinChina LaboratoryofErosionControl GraduateSchoolofAgricultureKyotoUniversityKyoto6068502Japan InstituteofEnvironmentalScience BeijingNormalUniversityBeijing100875China

In order to understand the process of surface erosion and its changing characteristics, a sprinkling experiment is conducted on a bare slope in Mt. Tanakami. Based on the measurements and analysis of runoff, mean soil erosion depth sediment yield and semiment transport, etc., the characteristics in the process of surface erosion in the experimental area are as follows: the occurrence of sediment discharge is interrupted, with a saturated overland-flow surface runoff; the mean erosion depth is 0.086 2 cm, which is thicker compared with other areas in Mt. Tanakmi; sediment yield is 431. 283 m3·km?2, whose process is detachment-limited, and the type of sediment transport is a sediment flow. Key words runoff - soil erosion depth - sediment yield - sediment transport - Mt. Tanakami CLC number S 157 Biography: ZHAO Wei (1975-), female, Ph. D candidate, Lecturer, now is working in College of Earth Sciences, Jilin University, research dircetion: physical geography, environmental planning and management

关键词： runoff soil erosion depth sediment yield sediment transport Mt. Tanakami

Optimization of Crosswalk Width Based on Bi-Directional Pedestrian Crossing Time at Signalized Intersections

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Journal of Beijing Institute of Technology 2018年第2期27卷 285-292页

作者： Ningbo Cao Yongheng Chen zhaowei Qu Liying Zhao Yanfei Li Qiujie yang College of Transportation Jilin UniversityChangchun 130022China Tianjin Transportation Research Institute Tianjin 300074China

The effects of the interactions between bi-directional pedestrians on the crossing time and the crosswalk width are studied. Firstly,the crossing process of bi-directional pedestrians is *** total crosswalk time is divided into a discharge time and a crossing time. The interactions between bi-directional pedestrians are quantified with the drag force theory. Then,a model is developed to study the crossing time based on the kinetic energy theory and momentum theory. Subsequently,the related parameters of the proposed model are calibrated with observed information. The relationships among crosswalk width,signal time,pedestrian volume and level of service are simulated with the proposed model. The results are verified and compared with other models. The proposed model has an absolute value of relative error of 9. 38%,which is smaller than that of the Alhajyaseen model（ 15. 26%） and Highway Capacity Manual（ HCM） model（ 12. 42%）. Finally,suggested crosswalk widths at different conditions are successfully estimated with the proposed crossing time model.

关键词： signalized crosswalks bi-directional pedestrian drag force theory crossing time cross-walk width

KINEMATICS FEATURE ANALYSIS OF A 3-DOF COMPLIANT MECHANISM FOR MICRO MANIPULATION

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Chinese Journal of Mechanical Engineering 2004年第1期17卷 127-131页

作者： YuJingjun HuYida BiShusheng ZongGuanghua zhaowei RoboticsInstitute BeijingUniversityofAeronauticsandAstronauticsBeijing100083China DepartmentofMechanicalEngineering UniversityofSaskatchewanSaskatoonSKS7N5A9Canada

Kinematics and its related issues of a 3-DOF in-parallel compliant mechanismare focused on. The micro manipulation application that requires high accuracy is developed. Designof the developed micromanipulator is based on the modified Delta mechanism. The main advantages ofthis manipulator are the use of only revolute flexure hinges and the capability to produce puretranslation theoretically. The aim is to develop an efficient kinematic model used for positioningcontrol. For this purpose, the Jacobian matrix relating the end effector position with the actuatordisplacements is obtained by both theoretical derivation and experiment. Aiming at the abnormalityin the motion capabilities of the micromanipulator found in calibration experiment, the mobility ofthe compliant mechanism on a theoretical level is analyzed by using the matrix method and screwtheory. Both the experimental and theoretical results have verified that the compliant mechanismdoes have rotational motion.

关键词： Compliant mechanism Kinematics Calibration Mobility

Hydrogen storage performance of LaNi3.95Al0.75Co0.3 alloy with different preparation methods

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Progress in Natural Science:Materials International 2022年第2期32卷 206-214页

作者： Lijun Lv Jian Lin Guo yang zhaowei Ma Linhua Xu Xiujie He Xingbo Han Wei Liu Shanghai Institute of Applied Physics Chinese Academy of Sciences Sino-French Institute of Nuclear Engineering and Technology Sun Yat-sen University

Rare-earth AB5-type La-Ni-Al hydrogen storage alloys are widely studied due to their extensive application potentials in hydrogen isotope storage,hydrogen isotope isolation and hydrogen compressors,*** hydriding/dehydriding kinetics,easily activation,high reversibility are important factors for their practical ***,their overall hydrogen storage performance,especially plateau pressure and hydrogen absorption/desorption durability need to be further *** this study,the microstructures and the hydrogen storage properties of as-cast,annealed,and melt-spun LaNi3.95Al0.75Co0.3alloys were *** experimental results of XRD and SEM showed that all alloys contained a pure CaCu5type hexagonal structure LaNi4Al *** cell volume increased in an order of annealed> melt-spun> as-cast,resulting in a lower hydrogen absorption/desorption plateau pressure and a more stable hydride *** hydrogen storage capacity of three alloys was almost the *** slope factor of the annealed and melt-spun alloys is smaller than the as-cast alloy,indicating that heat-treatment process can make the alloys more *** the cycle stability of the alloys,the hydrogen absorption rate of the annealed alloy and melt-spun alloy was much faster than that of the as-cast alloy after 500 *** melt-spun alloy showed high pulverization resistance during hydrogen absorption/desorption,and exhibited an excellent cycling retention of 99% after 500 cycles,suggesting that melt-spinning process can enhance the cycle stability and improve the cycle life of the alloy.

关键词： Hydrogen storage alloy LaNi 4.25 Al 0.75 Annealing process Melt-spinning